[Mechanisms and prognosis of neutropenia in Felty's syndrome. 27 cases (author's transl)].

Twenty patients with Felty's syndrome were investigated. Isotopic studies of polymorphonuclear neutrophils, bone marrow biopsies and autoradiographies, and cultures of granulous stem cells showed that neutropenia resulted from three mechanisms acting simultaneously: hypermargination of the neutrophils predominantly in the spleen, decreased production of granulocytes in the bone marrow, and peripheral hyperdestruction of the neutrophils. Anti-granulocyte antibodies were detected in 3/12 patients. Other factors present in the serum of 2/4 patients seem capable of inhibiting the growth of granulocytic stem cells. Secondary bacterial infection (77%) may explain the severity of the prognosis: 13 out of 27 patients died 4 years on average after neutropenia was diagnosed.